BoilerFaultCodesTechnical description
No Heating demand from external controls 24V
What causes this fault?
This code appears when your boiler is ready to work but hasn't received a signal from your wall thermostat or timer to start heating the radiators. The most common reason is that the batteries in your wireless thermostat have run out or the timer is set to an 'off' period. It can also happen if the communication between your heating controls and the boiler has been interrupted.
This code is often seen during the first cold snap of autumn when homeowners first try to turn their heating back on after the summer break.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your heating programmer or timer is set to 'ON' or 'AUTO'.Replace the batteries in your wireless room thermostat if the screen is blank or showing a low battery icon.